Question

What is the moment of inertia of a pendulum with a mass of `4 kg` that is `3 m` from the pivot?

Answer 1

`I = 36 kg*m^2`

Explanation:

The typical pendulum's "bob" is size is much smaller than the length of the pendulum shaft. Assuming that to be the case here, the mass is a point mass, and the moment of inertia is given by

`I = M*R^2`

Therefore, `I = 4 kg*(3 m)^2 = 36 kg*m^2`

I hope this helps,
Steve